Saturated vapor pressure, critical evaporation temperature and evaporation loss rate of Fe-Ga alloy were calculated under different conditions of Ga and Fe contents with activity coefficients. The relationship between...Saturated vapor pressure, critical evaporation temperature and evaporation loss rate of Fe-Ga alloy were calculated under different conditions of Ga and Fe contents with activity coefficients. The relationship between the change of Ga content and melting time was determined. The results demonstrated that saturated vapor pressure of Ga was higher than that of Fe under the same conditions. The difference value of critical evaporation temperature of Ga with and without Ar was nearly 800 K. The critical evaporation temperature of Fe was higher than that of Ga under vacuum, indicating that Ga was more volatile than Fe. At 1800 K, the evaporation rate of Ga was 84 times higher than that of Fe in the melt of Fe81Ga19 alloy. Under this condition, the change of Ga content and smelting time kept a linear relationship. The higher the temperature was, the faster the Ga content decreased, which was consistent with theoretical calculations.展开更多
CuCr alloys are important contact materials, but all conventional preparing methods have disadvantages and mismatch the requirements for mass production and high properties. The CuCr25 alloys were prepared by means of...CuCr alloys are important contact materials, but all conventional preparing methods have disadvantages and mismatch the requirements for mass production and high properties. The CuCr25 alloys were prepared by means of arc smelting in vacuum, and their microstructures, physical properties as well as dielectric strength were investigated. The experimental results show that vacuum arc smelting is an ideal method to produce CuCr25 contact alloys with fine microstructure, low gas content, high density and dielectric strength. Meanwhile, with the high productivity and low cost, CuCr25 contact materials can be produced with mass production through vacuum arc smelting method.展开更多
基金Item Sponsored by National Natural Science Foundation of China(51161019)Project of Department of Science and Technology of Jiangxi Province of China(20133BBE50011)Project of Department of Science & Technology of Jiangxi Province of China(20141BDH80025)
文摘Saturated vapor pressure, critical evaporation temperature and evaporation loss rate of Fe-Ga alloy were calculated under different conditions of Ga and Fe contents with activity coefficients. The relationship between the change of Ga content and melting time was determined. The results demonstrated that saturated vapor pressure of Ga was higher than that of Fe under the same conditions. The difference value of critical evaporation temperature of Ga with and without Ar was nearly 800 K. The critical evaporation temperature of Fe was higher than that of Ga under vacuum, indicating that Ga was more volatile than Fe. At 1800 K, the evaporation rate of Ga was 84 times higher than that of Fe in the melt of Fe81Ga19 alloy. Under this condition, the change of Ga content and smelting time kept a linear relationship. The higher the temperature was, the faster the Ga content decreased, which was consistent with theoretical calculations.
文摘CuCr alloys are important contact materials, but all conventional preparing methods have disadvantages and mismatch the requirements for mass production and high properties. The CuCr25 alloys were prepared by means of arc smelting in vacuum, and their microstructures, physical properties as well as dielectric strength were investigated. The experimental results show that vacuum arc smelting is an ideal method to produce CuCr25 contact alloys with fine microstructure, low gas content, high density and dielectric strength. Meanwhile, with the high productivity and low cost, CuCr25 contact materials can be produced with mass production through vacuum arc smelting method.
